1,305 research outputs found
Simultaneous measurement of quality factor and wavelength shift by phase shift microcavity ring down spectroscopy
Optical resonant microcavities with ultra high quality factors are widely
used for biosensing. Until now, the primary method of detection has been based
upon tracking the resonant wavelength shift as a function of biodetection
events. One of the sources of noise in all resonant-wavelength shift
measurements is the noise due to intensity fluctuations of the laser source. An
alternative approach is to track the change in the quality factor of the
optical cavity by using phase shift cavity ring down spectroscopy, a technique
which is insensitive to the intensity fluctuations of the laser source. Here,
using biotinylated microtoroid resonant cavities, we show simultaneous
measurement of the quality factor and the wavelength shift by using phase shift
cavity ring down spectroscopy. These measurements were performed for
disassociation phase of biotin-streptavidin reaction. We found that the
disassociation curves are in good agreement with the previously published
results. Hence, we demonstrate not only the application of phase shift cavity
ring down spectroscopy to microcavities in the liquid phase but also
simultaneous measurement of the quality factor and the wavelength shift for the
microcavity biosensors in the application of kinetics measurements
Genetic associations of PPARGC1A with Type 2 Diabetes : differences among populations with African origins
The aim of this study was to assess the differences in correlation of PPARGC1A polymorphisms with type 2 diabetes (T2D) risk in adults of African origins: African Americans and Haitian Americans. The case-control study consisted of >30 years old, self-identified Haitian Americans (n=110 cases and n=116 controls) and African Americans (n=124 cases and n=122 controls) living in South Florida with and without T2D. Adjusted logistic regression indicated that both SNP rs7656250 (OR = 0.22, P=0.005) and rs4235308 (OR = 0.42, P=0.026) showed protective association with T2D in Haitian Americans. In African Americans, however, rs4235308 showed significant risk association with T2D (OR = 2.53, P=0.028). After stratification with sex, in Haitian Americans, both rs4235308 (OR = 0.38, P=0.026) and rs7656250 (OR = 0.23, P=0.006) showed protective association with T2D in females whereas in African American males rs7656250 had statistically significant protective effect on T2D (OR = 0.37, P=0.043). The trends observed for genetic association of PPARGC1A SNPs, rs4235308, and rs7656250 for T2D between Haitian Americans and African Americans point out differences in Black race and warrant replicative study with larger sample size
Accurate determination of the quality factor and tunneling distance of axisymmetric resonators for biosensing applications
Due to ultra high quality factor (), axisymmetric optical
microcavities are popular platforms for biosensing applications. It has been
recently demonstrated that a microcavity biosensor can track a biodetection
event as a function of its quality factor by using phase shift cavity ring down
spectroscopy (PS-CRDS). However, to achieve maximum sensitivity, it is
necessary to optimize the microcavity parameters for a given sensing
application. Here, we introduce an improved finite element model which allows
us to determine the optimized geometry for the PS-CRDS sensor. The improved
model not only provides fast and accurate determination of quality factors but
also determines the tunneling distance of axisymmetric resonators. The improved
model is validated numerically, analytically, and experimentally.Comment: Published in Optics Express, April 2, 201
Improvement of brinjals (Solanum Melongena, L.) by selection in the Bombay province
This article does not have an abstract
Lifestyle Behaviors and Self-Rated Health: The Living for Health Program
Background. Lack of adherence to dietary and physical activity guidelines has been linked to an increase in chronic diseases in the United States (US). The aim of this study was to assess the association of lifestyle behaviors with self-rated health (SRH). Methods. This cross-sectional study used self-reported data from Living for Health Program ( 1,701) which was conducted from 2008 to 2012 in 190 health fair events in South Florida, US. Results. Significantly higher percent of females as compared to males were classified as obese (35.4% versus 27.0%), reported poor/fair SRH (23.4% versus 15.0%), and were less physically active (33.9% versus 25.4%). Adjusted logistic regression models indicated that both females and males were more likely to report poor/fair SRH if they consumed 2 servings of fruits and vegetables per day (, 95% CI 1.30–3.54; , 95% CI 1.12–7.35, resp.) and consumed mostly high fat foods (, 95% CI 1.03–2.43; , 95% CI 1.67–2.43, resp.). The association of SRH with less physical activity was only significant in females (, 95% CI 1.17–2.35). Conclusion. Gender differences in health behaviors should be considered in designing and monitoring lifestyle interventions to prevent cardiovascular diseases
Imaging Modalities for the Glenoid Track in Recurrent Shoulder Instability: A Systematic Review
A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Background:
The glenoid track (GT) concept illustrates how the degree of glenoid bone loss and humeral bone loss in the glenohumeral joint can guide further treatment in a patient with anterior instability. The importance of determining which lesions are at risk for recurrent instability involves imaging of the glenohumeral joint, but no studies have determined which type of imaging is the most appropriate.
Purpose/Hypothesis:
The purpose of this study was to determine the validity and accuracy of different imaging modalities for measuring the GT in shoulders with recurrent anterior instability. We hypothesized that 3-dimensional computed tomography (3D-CT) would be the most accurate imaging technique.
Study Design:
Systematic review; Level of evidence, 4.
Methods:
A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed, Scopus, Medline, and Cochrane libraries between database inception and July 2019. We included all clinical trials or cadaveric studies that evaluated imaging modalities for assessing the GT.
Results:
A total of 13 studies were included in this review: 1 study using 2-dimensional CT, 6 studies using 3D-CT, 4 studies using magnetic resonance imaging (MRI), 1 study using magnetic resonance arthrography (MRA)/MRI, and 1 study combining CT and MRI. The mean sensitivity, specificity, and accuracy for 2D-CT was 92%, 100%, and 96%, respectively. For MRI, the means were 72.2%, 87.9%, and 84.2%, respectively. No papers included 3D-CT metrics. The mean intraclass correlation coefficients (ICCs) for intraobserver reliability were 0.9046 for 3D-CT and 0.867 for MRI. ICCs for interobserver reliability were 0.8164, 0.8845, and 0.43 for 3D-CT, MRI, and MRA/MRI, respectively.
Conclusion:
There is evidence to support the use of both CT and MRI imaging modalities in assessing the GT. In addition, few studies have compared radiographic measurements with a gold standard, and even fewer have looked at the GT concept as a predictor of outcomes. Thus, future studies are needed to further evaluate which imaging modality is the most accurate to assess the GT
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